Which part of this excerpt from President Franklin D. Roosevelt's "Four Freedoms" speech demonstrates the use of logos?
Let us say to the democracies: "We Americans are vitally concerned in your defense of freedom. We are putting forth our energies, our resources and our organizing powers to give you the strength to regain and maintain a free world. We shall send you, in ever-increasing numbers, ships, planes, tanks, guns. This is our purpose and our pledge."

In fulfillment of this purpose we will not be intimidated by the threats of dictators that they will regard as a breach of international law or as an act of war our aid to the democracies which dare to resist their aggression. Such aid . . . such aid is not an act of war, even if a dictator should unilaterally proclaim it so to be.

And when the dictators, if the dictators, are ready to make war upon us, they will not wait for an act of war on our part. They did not wait for Norway or Belgium or the Netherlands to commit an act of war.

Their only interest is in a new one-way international law, which lacks mutuality in its observance, and, therefore, becomes an instrument of oppression.

The happiness of future generations of Americans may well depend upon how effective and how immediate we can make our aid felt. No one can tell the exact character of the emergency situations that we may be called upon to meet. The Nation's hands must not be tied when the Nation's life is in danger.

Yes, and we must all prepare–all of us prepare–to make the sacrifices that the emergency– almost as serious as war itself–demands. Whatever stands in the way of speed and efficiency in defense–in defense preparations of any kind–must give way to the national need.